fix: unbounded WebSocket message reads allow memory exhaustion - #16
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I3eg1nner wants to merge 3 commits into
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fix: unbounded WebSocket message reads allow memory exhaustion#16I3eg1nner wants to merge 3 commits into
I3eg1nner wants to merge 3 commits into
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Both the native and mongoose backends read WS messages without a size limit. A malicious client can exhaust server memory: - native: msg.read_all() buffers the entire message - mongoose: Array::make(ws_msg_body_len(), ...) allocates based on the frame header's declared length, which can be arbitrarily large Reuse the existing read_body_limited() for native text/binary messages. For mongoose, reject frames whose declared size exceeds max_body_size before allocating. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
…runcated prefix 1. Mongoose __ws_emit "message" branch had no size check — text messages of any size reached the handler. Add the same ws_max_body_size guard as the binary branch. 2. Native read_body_limited returns a truncated prefix when a message exceeds max_body_size (e.g. 8192 bytes of a 10000-byte message). Add read_ws_limited that returns None on overflow; the WS handler now silently drops oversized messages instead of dispatching partial data. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
…ces max_body_size Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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WebSocket message handling has no size limit in either backend:
header's declared length, allocating arbitrarily large buffers
A single malicious client can OOM the server.
Fix: reuse the existing read_body_limited() for native WS reads.
For mongoose, reject frames exceeding max_body_size before allocation.
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